Natural Selection MS-LS4-6

Grade 8 - NGSS - CA

A trait that helps an organism survive in its environment

Adaptation

A trait that helps an organism survive in its environment. Adaptation. In simple terms, adaptation is when animals or plants change over time to better fit their environment.

The proportion of one allele of a gene compared to other alleles of the same gene

Allele frequency

The proportion of one allele of a gene compared to other alleles of the same gene. Allele frequency. Allele frequency is how often a specific version of a gene shows up in a group.

The largest population that an environment can support

Carrying capacity

The largest population that an environment can support. Carrying capacity. Carrying capacity is the maximum number of living things an area can support without running out of resources.

A dramatic population increase in a short time

Exponential growth

A dramatic population increase in a short time. Exponential growth. Exponential growth means the population multiplies rapidly over time, like in a chain reaction.

The ability of an organism to survive and reproduce in its environment

Fitness

The ability of an organism to survive and reproduce in its environment. Fitness. Fitness means how well an organism can live and have babies in its environment.

States that allele frequencies in a population are constant unless a factor causes change

Hardy Weinberg principle

States that allele frequencies in a population are constant unless a factor causes change. Hardy Weinberg principle. The Hardy-Weinberg principle explains how the genetic makeup of a large, random-mating population will stay the same over generations unless influenced by outside factors.

When population growth starts slow, then sees exponential growth, then slows again

Logistic growth

When population growth starts slow, then sees exponential growth, then slows again. Logistic growth. In simple terms for Grade 8, logistic growth is how a population grows quickly at first, then slows down as resources run out.

The individuals best suited to survive in an environment

Natural selection

The individuals best suited to survive in an environment. Natural selection. Natural selection is the process where organisms with traits better suited to their environment are more likely to survive and reproduce.

Any characteristic of an organism

Trait

Any characteristic of an organism. Trait. In Grade 8 science, a trait is a feature or quality of a living thing, like brown eyes or tall height.